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Project Gutenberg was started by Michael Hart in 1971 with the digitization of the United States Declaration of Independence.[4] Hart, a student at the University of Illinois, obtained access to a Xerox Sigma Vmainframe computer in the university's Materials Research Lab. Through friendly operators, he received an account with a virtually unlimited amount of computer time; its value at that time has since been variously estimated at $100,000 or $100,000,000.[5] Hart has said he wanted to "give back" this gift by doing something that could be considered to be of great value. His initial goal was to make the 10,000 most consulted books available to the public at little or no charge, and to do so by the end of the 20th century.[6]

By the mid-1990s, Hart was running Project Gutenberg from Illinois Benedictine College. More volunteers had joined the effort. All of the text was entered manually until 1989 when image scanners and optical character recognition software improved and became more widely available, which made book scanning more feasible.[7] Hart later came to an arrangement with Carnegie Mellon University, which agreed to administer Project Gutenberg's finances. As the volume of e-texts increased, volunteers began to take over the project's day-to-day operations that Hart had run.

Italian volunteer Pietro Di Miceli developed and administered the first Project Gutenberg website and started the development of the Project online Catalog. In his ten years in this role (1994–2004), the Project web pages won a number of awards, often being featured in "best of the Web" listings, and contributing to the project's popularity.[8]

Project Gutenberg founder, Michael Hart, died on 6 September 2011 at his home at Urbana, Illinois at the age of 64.[9]

In 2000, a non-profit corporation, the Project Gutenberg Literary Archive Foundation, Inc. was chartered in Mississippi to handle the project's legal needs. Donations to it are tax-deductible. Long-time Project Gutenberg volunteer Gregory Newby became the foundation's first CEO.[10]

Also In 2000, Charles Franks founded Distributed Proofreaders (DP), which allowed the proofreading of scanned texts to be distributed among many volunteers over the Internet. This effort greatly increased the number and variety of texts being added to Project Gutenberg, as well as making it easier for new volunteers to start contributing. DP became officially affiliated with Project Gutenberg in 2002.[11] As of 2007[update], the 10,000+ DP-contributed books comprised almost a third of the nearly 48,300 books in Project Gutenberg.

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In December 2003, a DVD was created containing nearly 10,000 items. At the time, this almost represented the entire collection. In early 2004, the DVD also became available by mail.

In July 2007, a new edition of the DVD was released containing over 17,000 books, and in April 2010, a dual-layer DVD was released, containing nearly 30,000 items.

The majority of the DVDs, and all of the CDs mailed by the project were recorded on recordable media by volunteers. However, the new dual layer DVDs were manufactured, as it proved more economical than having volunteers burn them. As of October 2010[update], the project has mailed approximately 40,000 discs.[13]

As of January 2015[update], Project Gutenberg claimed over 48,300 items in its collection, with an average of over fifty new e-books being added each week.[14] These are primarily works of literature from the Western cultural tradition. In addition to literature such as novels, poetry, short stories and drama, Project Gutenberg also has cookbooks, reference works and issues of periodicals.[15] The Project Gutenberg collection also has a few non-text items such as audio files and music notation files.[16]

Most releases are in English, but there are also significant numbers in many other languages. As of February 2013[update], the non-English languages most represented are: French, German, Finnish, Dutch, Portuguese, and Chinese.[3]

Whenever possible, Gutenberg releases are available in plain text, mainly using US-ASCIIcharacter encoding but frequently extended to ISO-8859-1 (needed to represent accented characters in French and Scharfes s in German, for example). Besides being copyright-free, the requirement for a Latin (character set) text version of the release has been a criterion of Michael Hart's since the founding of Project Gutenberg, as he believes this is the format most likely to be readable in the extended future.[17] Out of necessity, this criterion has had to be extended further for the sizable collection of texts in East Asian languages such as Chinese and Japanese now in the collection, where UTF-8 is used instead.

Other formats may be released as well when submitted by volunteers. The most common non-ASCII format is HTML, which allows markup and illustrations to be included. Some project members and users have requested more advanced formats, believing them to be much easier to read. But some formats that are not easily editable, such as PDF, are generally not considered to fit in with the goals of Project Gutenberg. Also Project Gutenberg has two options for master formats which can be submitted (from which all other files are generated), customized versions of the Text Encoding Initiative standard since 2005,[18] and reStructuredText, since 2011.[19]

Michael Hart said in 2004, "The mission of Project Gutenberg is simple: 'To encourage the creation and distribution of ebooks'".[2] His goal was, "to provide as many e-books in as many formats as possible for the entire world to read in as many languages as possible".[3] Likewise, a project slogan is to "break down the bars of ignorance and illiteracy",[21] because its volunteers aim to continue spreading public literacy and appreciation for the literary heritage just as public libraries began to do in the late 19th century.[22][23]

Project Gutenberg is intentionally decentralized. For example, there is no selection policy dictating what texts to add. Instead, individual volunteers work on what they are interested in, or have available. The Project Gutenberg collection is intended to preserve items for the long term, so they cannot be lost by any one localized accident. In an effort to ensure this, the entire collection is backed-up regularly and mirrored on servers in many different locations.[24]

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The text files use the legacy format of plain ASCII, wrapped at 65–70 characters, with paragraphs separated by a double-line break. In recent decades the resulting relatively bland appearance and the lack of a markup possibility have often been perceived as a drawback of this format.[25] Project Gutenberg attempts to address this by making many texts available in HTML and PDF versions as well, but faithful to the mission, of offering data which is easy to handle with computer code, plain ASCII text remains the most important format.

While the works in Project Gutenberg represent a valuable sample of publications that span several centuries, there are some issues of concern for linguistic analysis. Some content may have been modified by the transcriber because of editorial changes or corrections (such as to correct for obvious proof-setting or printing errors). The spelling may also have been modified to conform with current practices (although the intent by Project Gutenberg,[26] and by Distributed Proofreaders,[1] is to preserve the original text and where possible the formatting). This can mean that the works may be problematic when searching for older grammatical usage. Finally, the collected works can be weighted heavily towards certain authors (such as Charles Dickens), while others are barely represented.[27]

In March 2004, a new initiative was begun by Michael Hart and John S. Guagliardo[28] to provide low-cost intellectual properties. The initial name for this project was Project Gutenberg 2 (PG II), which created controversy among PG volunteers because of the re-use of the project's trademarked name for a commercial venture.[10]

All affiliated projects are independent organizations which share the same ideals, and have been given permission to use the Project Gutenberg trademark. They often have a particular national, or linguistic focus.[29]

Project Gutenberg Consortia Center is an affiliate specializing in collections of collections. These do not have the editorial oversight or consistent formatting of the main Project Gutenberg. Thematic collections, as well as numerous languages, are featured.[32]

Project Gutenberg Russia is a project that aims to collect public domain books in Slavic languages, Russian in particular. The discussion of the project and its legal side began in April 2012. The word Rutenberg is a combination of words "Russia" and "Gutenberg".[38]

^According to gutindex-2006, there were 1,653 new Project Gutenberg items posted in the first 33 weeks of 2006. This averages out to 50.09 per week. This does not include additions to affiliated projects.

^Various Project Gutenberg FAQs allude to this. See, for example: Staff. "File Formats FAQ". Retrieved 2 November 2012. You can view or edit ASCII text using just about every text editor or viewer in the world. [...] Unicode is steadily gaining ground, with at least some support in every major operating system, but we're nowhere near the point where everyone can just open a text based on Unicode and read and edit it.